This invention relates to a suction device for an endoscope allowing for easy brushing of the interior of a suction pipe.
An endoscope is generally provided with a suction tube, through which, for example, a viscous liquid, filth and blood retained in the coeliac cavity are drawn off. This suction tube is generally divided into a first section constituting the upstream region extending from the control section of the endoscope to the tip of the distal end of the insertion section and a second section constituting the downstream region extending from said control section to the connector connected to the end of the universal cord.
Those portions of the first and second tube sections which are held in the control section are partly connected to a suction changeover valve provided in the control section. Operation of said suction changeover valve effects suction.
Recently, problems have arisen because of a hospital infection resulting from HB antigens. To avoid the occurrence of such event, it is strongly recommended not only to pass a disinfecting liquid through a suction tube generally contaminated by patient's blood, but also to force a brush into the suction tube to clean its interior. To this end, it is contemplated to detachably fit a piston constituting the suction changeover valve into a cylinder and, when the piston is removed, to insert a brush from a cylinder open at the control section into the upstream region of the suction tube partly connected to the cylinder there to clean the interior of said upstream region. When, however, a brush is inserted into a suction tube at the other end of the first tube region open to the distal end of the insertion section or at the other end of the second tube region open to the connector, then the filth remaining in the suction tube tends to leak from the suction changeover valve to the control section. If the angle knob and eyepiece provided in the control section are contaminated, then much effort will be needed to wash and disinfect these members. When, therefore, the suction tube is to be brushed, it is preferable to insert a brush from the cylinder holding the detachable suction changeover valve into both upstream and downstream tube regions.
With the conventional endoscope, however, either upstream or downstream region the suction tube is connected at one end to the peripheral wall of the cylinder. Therefore, one end of that suction tube region which is connected to the peripheral wall of the cylinder is open in a direction intersecting the axis of the cylinder at right angles. Consequently considerable difficulties are encountered in inserting a brush into said suction tube region. If it is tried to forcefully pass a brush through said suction tube region, the brush will be damaged at once.